The semiconductor fabrication industry has an interest in depositing barium strontium titanate films (“BST”) for constructing various electronic devices in integrated circuits. The industry has sought precursors of barium strontium and titanium that are stable, liquid and readily decompose under standard deposition conditions leaving high purity BST films and removing in the vapor phase the remainder of the precursors of barium, strontium and titanium, typically in the form of ligands that reversibly bind the metals until the deposition conditions are provide wherein the metal is deposited from the ligand precursor resulting in essentially deposited metal and volatile, gas phase leaving groups constituting the ligand that bound the metal in the precursor form or decomposition components of the ligand which still exhibit the properties of being good leaving groups that do not contaminate the deposited BST film and typically leave as volatile, gaseous groups.
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